Wide angle deflection yoke quadrupole windings

ABSTRACT

A deflection yoke for a cathode ray tube includes a frustroconical core of magnetic material with a first pair of windings toroidally wrapped in a first level on the core, a second pair of windings toroidally wrapped on the core and interleaved with the first pair of windings to provide a solid first level of windings and forming a second level, and first, second, third, and fourth quadrupole windings toroidally wrapped on the core and interleaved with the second pair of windings of the second level whereby a minimum number of levels are employed for affixing all of the windings to the core.

[ 1 Nov. 25, 1975 WIDE ANGLE DEFLECTION YOKE QUADRUPOLE WINDINGS {75] Inventors: Frederick A. Hovey; Charles E.

Torsch, both of Geneva, NY.

[73] Assignee: GTE Sylvania incorporated,

Stamford, Conn.

[22] Filed: Nov. 7, 1974 [211 Appl. No.: 521,698

[52] US. Cl. 335/213 [51] Int. Cl. 01F 7/00 [58] Field of Search 335/213 [56] References Cited UNITED STATES PATENTS 3,792,305 2/1974 Lister 335/2l3 Primary ExaminerHarold Broome Attorney, Agent, or FirmN0rman J. O'Malley; Thomas H. Buffton; Robert T. Orner {5 7] ABSTRACT A deflection yoke for a cathode ray tube includes a frustro-conical core of magnetic material with a first pair of windings toroidally wrapped in a first level on the core, a second pair of windings toroidally wrapped on the core and interleaved with the first pair of windings to provide a solid first level of windings and form ing a second level, and first, second, third, and fourth quadrupole windings toroidally wrapped on the core and interleaved with the second pair of windings of the second level whereby a minimum number of levels are employed for affixing all of the windings to the core.

7 Claims, 2 Drawing Figures US. Patent Nov. 25, 1975 3,922,626

WIDE ANGLE DEFLECTION YOKE QUADRUPOLE WINDINGS BACKGROUND OF THE INVENTION Generally, this invention relates to toroid-wound deflection yokes for a cathode ray tube utilized in a television receiver. More particularly, the invention is concerned with a toroid-wound deflection yoke which includes quadrupole as well as horizontal and vertical de flection windings with the thickness of the windings such that a toroid-wound core is closely fitted to the cathode ray tube.

It is well known in the art to provide a deflection yoke for a cathode ray tube wherein pairs of horizontal windings and pairs of vertical windings are toroidally wound on a magnetic core. Also, it is well known that pairs of horizontal and vertical windings are, in some instances, insufficient for providing the desired convergence of the electron beams in a cathode ray tube. Thus, added convergence capability is effected by including so-called quadrupole windings wherein first, second, third and fourth windings are disposed and approximately centered on the horizontal and vertical axis of the deflection yoke.

In the known forms of toroid-wound deflection yokes wherein horizontal, vertical, and quadrupole deflection windings are employed, the winding patterns are of a nature such that the quadrupole windings are frequently in a third or fourth layer on a magnetic core. In other words, the horizontal and vertical deflection windings are affixed to the magnetic core in two levels while the quadrupole windings occupy a third or often a third and fourth level on the core.

Unfortunately, the increased number of levels on the core due to the quadrupole windings increases the thickness of the windings whereupon the deflection yoke cannot be closely fitted to the contour of the cathode ray tube. As a result, purity adjustment, which is maximized for close fitting core and cathode ray tube components, is deleteriously affected by the added thickness of the windings. Moreover, a deterioration of purity clue to increased winding thickness is accompanied by an increase in undesired neck shadow or raster corner cutting.

In another known instance, US. Pat. No. 3,792,305, issued Dec. 23, 1971 to John W. Lister, the horizontal, vertical, and quadrupole windings are affixed to the magnetic core in two levels. However, a plurality of unused spaces remain in the first level whereupon efficient utilization of available spaces is deleteriously affected. Moreover, the problems of maintaining correct and desired turn spacing and wire tension are undesirably increased.

OBJECTS AND SUMMARY OF THE INVENTION An object of the present invention is to provide an enhanced deflection yoke for a cathode ray tube. Another object of the invention is to improve the compatability of a deflection yoke and cathode ray tube. Still another object of the invention is to improve the purity adjustment capability of a cathode ray tube utilizing a deflection yoke which includes quadrupole windings. A further object of the invention is to minimize the windings levels and winding thickness of a deflection yoke having toroid-wound quadrupole windings.

These and other objects, advantages and capabilities are achieved in one aspect of the invention by a toroid- 2 wound deflection yoke having a winding pattern such that horizontal, vertical, and quadrupole deflection windings are all included in two levels of toroid windings on a magnetic core.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates a deflection yoke with winding toroid-wound on a core of magnetic material; and

FIG. 2 is a cross-sectional illustration of a quadrant of a toroid-wound deflection yoke which includes a preferred embodiment of the invention.

PREFERRED EMBODIMENT OF THE INVENTION For a better understanding of the present invention, together with other and further objects, advantages and capabilities thereof, reference is made to the following disclosure and appended claims in connection with the accompanying drawings.

Referring to the drawings, FIG. I illustrates a deflection yoke formed to telescope over the neck portion of a cathode ray tube. The yoke includes a core 5 of magnetic material which is preferably frustro-conical in shape. A plurality of windings 7 are disposed in toroidwound fashion on the core 5 and the core 5 and windings 7 as formed to fit closely to the contour of a cathode ray tube.

In a preferred embodiment, the plurality of windings 7 include a pair of horizontal windings disposed on opposite sides ofa vertical axis, a pair of vertical windings disposed on opposite sides of a horizontal axis, and first, second, third, and fourth quadrupole windings each substantially centered on one of the horizontal and vertical axes. In a well-known manner, the horizontal windings are connected to a source of deflection signals having a normal horizontal scan rate or frequency, the vertical windings are connected to a source of deflection signals having a normal vertical scan rate or frequency, and the quadrupole windings are series connected to one another and to a source of deflection signals having a combined horizontal and vertical scan rate or frequency.

As will be recognized by those skilled in the art, the horizontal and vertical windings are substantially symmetrical to one another and disposed on opposite sides of the vertical and horizontal axes respectively. Moreover, the quadrupole windings associated with one another along one axis and on opposite sides of the other axis are substantially similar to one another. As a result, the winding pattern of a single quadrant of the deflection yoke may be utilized to illustrate the total winding of the deflection yoke.

Referring to FIG. 2, one quadrant of a composite winding for a deflection yoke is illustrated. In this graphic illustration, all wire signs and spaces or voids between wires are of equal diameter but appear to be of different size in order to clearly indicate each separate horizontal, vertical, and quadrupole winding. Ordinarily, the horizontal, vertical, and quadrupole winding are nested" or the turns of one winding disposed in the voids of another winding. Herein, a horizontal deflection winding 9 is substantially centered on a horizontal axis H-H' and occupies a portion of a first levelextending to the vertical axis V-V'. This horizontal deflection winding 9 includes a plurality of spaced turns 8 with voids 10 intermediate the turns.

A vertical deflection winding I I is substantially centered about the vertical axis V-V' and extends toward the horizontal axis HH'. This vertical deflection wind ing 11 includes a plurality of spaced turns 12 which are disposed in the voids intermediate the turns of the horizontal deflection winding 9 of the first level of turns 12 and in spaced array on a second level of turns.

Additionally, the quadrupole windings 13 are wound in a manner such that they are disposed within the spaces intermediate the turns 12 of the vertical deflection winding 11 of the second level of windings. Thus, the horizontal deflection windings 9 occupy a portion of one level of windings, the quadrupole windings l3 occupy a portion of a second level of windings, and the vertical deflection windings 11 are interleaved with the horizontal windings 9 to provide a solid first level of windings and with the quadrupole windings 13 of the second level of windings.

In this manner, there is provided a unique deflection yoke for a cathode ray tube wherein horizontal, vertical, and quadrupole windings are all included in two levels of windings. As a result, the horizontal windings are rendered more impervious to displacement by subsequent superpositioned wires clue to the occupancy of the voids intermediate the turns whereby a solid first level of turns is provided. Similarly. the deposition of the quadrupole windings in the voids of the vertical windings prevents undesired displacement of the turns of the second level of turns.

More importantly, the deflection yoke is more readily and more closely fitted to the contour of the cathode ray tube because of the reduced thickness of the windings. As a result, the range of purity adjustment is maximized, undesired neck shadow is reduced, wire length and cost is minimized to effect economy for a given performance, and the ratio of inductance to resistance is maximized while distributed capacity is desirably reduced.

While there has been shown and described what is at present considered the preferred embodiment of the invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention as defined by the appended claims.

What is claimed is:

1. A deflection yoke for a cathode ray tube comprisa first core of magnetic material formed to telescope over the neck portion of a cathode ray tube;

a first pair of windings having a plurality of spaced turns toroidally wrapped in a first level on said core, said pair of windings effecting electron beam deflection in a first plane;

a second pair of windings having a plurality of spaced turns toroidally wrapped on said core, said spaced turns interleaved with said spaced turns of said first pair of windings to provide a solid first level of turns and forming a second level of spaced turns; said pair of windings effecting electron beam deflection in a second plane perpendicular to said first plane; and

first, second, third, and fourth quadrupole windings having a plurality of spaced turns toroidally wrapped on said core and interleaved with said 4 spaced turns of said second level of said second pair of windings.

2. The deflection yoke of claim 1 wherein said first pair of windings effect electron beam deflection in a horizontal plane and said second pair of windings effect electron beam deflection in a vertical direction.

3. The deflection yoke of claim 1 wherein said first pair of windings are disposed in a single first level, said first, second, third, and fourth quadrupole windings are disposed in a single second level, and said second pair of windings are interspersed between said windings of said first and second levels.

4. The deflection yoke of claim 1 wherein said first and second pair of windings are substantially centered about planes extending along horizontal and vertical axes respectively and said first, second, third, and fourth quadrupole windings are substantially centered about said horizontal and vertical axes.

5. In a television receiver employing a cathode ray tube having a neck portion and an electron beam impinging a light emitting screen, a deflection yoke comprising:

a core of magnetic material of frustro-conical shape for telescoping over the neck portion of a cathode ray tube; pair of horizontal deflection windings oppositely disposed about the vertical axis of said core, each of said pair of windings having a plurality of spaced turns toroidally wrapped in a first level on said core for effecting deflection of an electron beam in a first direction;

a pair of vertical deflection windings oppositely disposed about the horizontal axis of said core each of said pair of windings having a plurality of spaced turns toroidally wrapped on said core and interleaved with said turns of said pair of horizontal deflection windings to provide a solid first level of turns and forming a second level of spaced turns; and

first, second, third, and fourth quadrupole windings toroidally wrapped on said core and centrally dis posed about said horizontal and vertical axis, said quadrupole windings interleaved with said turns of said second level of spaced vertical deflection windings.

6. The deflection yoke of claim 5 wherein said horizontal deflection windings and said first, second, third, and fourth quadrupole windings are in first and second levels on said core and said vertical deflection windings are interspersed between said first and second levels.

7. The deflection yoke of claim 5 wherein each of said pair of horizontal deflection windings is centrally disposed about said horizontal axis and oppositely disposed about said vertical axis, each of said pair of vertical deflection windings is centrally disposed about said vertical axis and oppositely disposed about said horizontal axis, and each one of said first, second, third, and fourth quadrupole windings is centrally disposed about one of said first and second axes.

i i i l 

1. A deflection yoke for a cathode ray tube comprising: a first core of magnetic material formed to telescope over the neck portion of a cathode ray tube; a first pair of windings having a plurality of spaced turns toroidally wrapped in a first level on said core, said pair of windings effecting electron beam deflection in a first plane; a second pair of windings having a plurality of spaced turns toroidally wrapped on said core, said spaced turns interleaved with said spaced turns of said first pair of windings to provide a solid first level of turns and forming a second level of spaced turns; said pair of windings effecting electron beam deflection in a second plane perpendicular to said first plane; and first, second, third, and fourth quadrupole windings having a plurality of spaced turns toroidally wrapped on said core and interleaved with said spaced turns of said second level of said second pair of windings.
 2. The deflection yoke of claim 1 wherein said first pair of windings effect electron beam deflection in a horizontal plane and said second pair of windings effect electron beam deflection in a vertical direction.
 3. The deflection yoke of claim 1 wherein said first pair of windings are disposed in a single first level, said first, second, third, and fourth quadrupole windings are disposed in a single second level, and said second pair of windings are interspersed between said windings of said first and second levels.
 4. The deflection yoke of claim 1 wherein said first and second pair of windings are substantially centered about planes extending along horizontal and vertical axes respectively and said first, second, third, and fourth quadrupole windings are substantially centered about said horizontal and vertical axes.
 5. In a television receiver employing a cathode ray tube having a neck portion and an electron beam impinging a light emitting screen, a deflection yoke comprising: a core of magnetic material of frustro-conical shape for telescoping over the neck portion of a cathode ray tube; a pair of horizontal deflection windings oppositely disposed about the vertical axis of said core, each of sAid pair of windings having a plurality of spaced turns toroidally wrapped in a first level on said core for effecting deflection of an electron beam in a first direction; a pair of vertical deflection windings oppositely disposed about the horizontal axis of said core each of said pair of windings having a plurality of spaced turns toroidally wrapped on said core and interleaved with said turns of said pair of horizontal deflection windings to provide a solid first level of turns and forming a second level of spaced turns; and first, second, third, and fourth quadrupole windings toroidally wrapped on said core and centrally disposed about said horizontal and vertical axis, said quadrupole windings interleaved with said turns of said second level of spaced vertical deflection windings.
 6. The deflection yoke of claim 5 wherein said horizontal deflection windings and said first, second, third, and fourth quadrupole windings are in first and second levels on said core and said vertical deflection windings are interspersed between said first and second levels.
 7. The deflection yoke of claim 5 wherein each of said pair of horizontal deflection windings is centrally disposed about said horizontal axis and oppositely disposed about said vertical axis, each of said pair of vertical deflection windings is centrally disposed about said vertical axis and oppositely disposed about said horizontal axis, and each one of said first, second, third, and fourth quadrupole windings is centrally disposed about one of said first and second axes. 